Thanksgiving forecast brings cooler temperatures

CATHY WURZER: Thanksgiving, of course, is tomorrow, and it seems as though we usually have some snow on the ground by now. But this warm November is making things look a little different. Joining us right now is our chief meteorologist, Paul Huttner. Hey, welcome back.

PAUL HUTTNER: Hey, good to talk to you again, Cathy. Happy Thanksgiving.

CATHY WURZER: Happy Thanksgiving, my friend. Is my memory foggy? It seems as though back in the day, we usually had a coating of snow on the ground for Thanksgiving.

PAUL HUTTNER: Yeah, November 18, on average, the first inch of snow, and the first inch of snow cover shortly after that. So your memory is accurate as usual.

CATHY WURZER: Thank you. I appreciate that. But not this November because it's been so ridiculously warm.

PAUL HUTTNER: Yeah, what November? I mean, this is very balmy. We're running 6.2 degrees warmer than average this month so far in the Twin Cities, and we're doing it again today. Already 43 in the Twin Cities with that breezy southwest wind. Our average high, 39. So we're already 4 degrees above the average for the day. And I think we'll hit about 48 in the Twin Cities today. It's already 52 at Appleton, Wheaton, Benson, and Madison at this hour.

And Cathy, this is the seventh straight warmer than average month in Minnesota. We started in May, and we will finish above average in November. There's no way, even though we're going to turn colder, that will drop below average for the month. So about 3 degrees warmer than average overall since May in Minnesota. And depending on how December comes in, this could be one of our top 10 warmest years on record in Minnesota, Cathy.

CATHY WURZER: Wow. Let's talk a bit about the Thanksgiving weekend forecast, if we could, because there are people who are going to be driving. Pretty good travel, it looks like, all weekend.

PAUL HUTTNER: Yeah, great news on the travel forecast. I don't think we're going to have any travel problems, really, across Minnesota. Maybe a few snow showers Sunday, especially in the northern half of Minnesota, but we're mild today, of course, 48 tomorrow-- blustery and colder. You'll feel a cold front come through. It'll be a good day for keeping those chilled beverages out on the porch. 34 degrees, northwest winds, 15 to 30 in the Twin Cities, 20 in northern Minnesota.

Same Friday, Saturday, Sunday. Low 30s for highs in the Twin Cities and southern Minnesota, 20s up north. We'll even fall into the teens for lows, Cathy, by Friday morning. So it also looks cold into early next week, but I'm seeing 40s again on some of the long range maps, as we move into the first week of December. So we could turn warmer than average again in early December.

CATHY WURZER: 40s in-- oh, OK. Wow.

PAUL HUTTNER: Yeah, we'll see.

CATHY WURZER: OK, let's shoehorn a couple of other issues into our conversation here. I noted that it looks like the plant hardiness zone changes were made for Minnesota. Is that right? Did I read that right?

PAUL HUTTNER: You did, and this is kind of interesting to me because it really reflects our climate extremes, if you will, and how they're being tempered over time because of climate change. So the plant hardiness zones represent the coldest temperature of the year on average in Minnesota, or in any given spot. And that sort of dictates what kind of plants can survive in Minnesota. And that's changing. Our average winter minimum temperature has warmed about 12 degrees overall since 1970.

So Twin Cities, for example, we've gone from an average, down around 30 below most years, to about 18 below. And that has changed our plant hardiness zone. We've moved from what they call 4B to zone 5, basically average lows from about 20 to 25 during the winter, the coldest temperature we see during the winter. Now more common to get 15 to 20 below in the Twin Cities.

And northern Minnesota, even a little more extreme, because they've moved from 3A to 3B, which means their average temp from 35 below to 40 below has gone from 30 to 35 below. It's getting harder to hit 40 below over much of northern Minnesota. Also, our friends in Chicago, Cathy, they've moved up a category as well. So warmer winters, one of the trademarks of climate change in the upper Midwest, is having an effect on our plant hardiness zones.

CATHY WURZER: Speaking of climate change, the world has reached 2 degrees Celsius for the first time?

PAUL HUTTNER: This is remarkable, and it's got a lot of climate folks kind of scratching their heads because it sort of popped up. The World Meteorological Organization and Copernicus, the EU Climate Group, says that November 17 and 18, so last weekend, the global average temperature was 2.07 degrees above Celsius, above pre-industrial times. So that's the first time that's ever been recorded, that two degree Celsius threshold.

Now, it doesn't mean that we've breached the Paris agreements. Those levels are over longer term averages, 2.0 Celsius over 20 years or so. But it's pretty concerning to people, and folks are asking why. I mean, ocean temperatures are at records this year. We know that 90% of climate warming has gone into the ocean. So some scientists are saying, is the ocean losing its capacity to absorb that extra heat, and more of it's getting into the atmosphere? That's one possible scenario.

Also, Cathy, the past 12 months, according to Climate Central, globally are the warmest on record, 1.3 degrees Celsius overall for that 12-month period. So interesting to watch. It may ease. El Niño may have a little part of this, but El Niño is just kind of getting cranked up and giving some additional heat to the atmosphere. We're going to need to watch this. So, hey, we're looking at that, right? We're looking at the plant hardiness zones in Minnesota. Can't grow palm trees here just yet, Cathy, but things are changing.

CATHY WURZER: I hope we never do grow palm trees here. By the way, because we have Thanksgiving tomorrow, no ClimateCast, is that right?

PAUL HUTTNER: I believe so. They might be throwing me a curveball, and it may be airing today. Sorry about that. It's just a scheduling thing, so we may hear it later today.

CATHY WURZER: OK, we'll see. I hope you really do have a nice, relaxing, restful Thanksgiving.

PAUL HUTTNER: And you too, Cathy. Have a great holiday weekend.

CATHY WURZER: You, too. That's MPR's chief meteorologist, Paul Huttner.